Muffler-filter apparatus for air flow passages



A. WEILAND Aug. 31, 1937.

MUFFLER FILTER APPARATUS FOR AIR FLOW PASSAGES 2 Sheets-Sheet l FiledSept. 16, 1935 INVENTOR A. 'IVe/Yana MUFFLER FILTER APPARATUS FOR AIRFLOW PASSAGES Filed sept. 1e, 1935 2 sheets-sheet 2 i Illl INVENTORPatentedI Aug. 31, 1937 UNITED STATES PATENT OFFICE Alfred Weiland,Philadelphia, Pa., Baldwin-Southwark Corporation,

tion of Delaware4 assigner to a corpora- Application September 16, 1935,Serial \No. 40,800

8 Claims. This invention relates generally to a combined noise silencingand filter apparatus for air flow passages particularly in aself-contained air conditioning unit. In air conditioning apparatus,especially of the self-contained room unit type having a compressor,condenser, evaporator and 4blower for circulating room air over theevaporator, there is likely to be some noise caused by the blower orcompressor mechanism or by the ow of air through the passages and overthe fins of the evaporator. It is particularly desirable to maintain allnoise at a minimum inasmuch as such a self-contained unit is placeddirectly within the room occupied by a person.

It is one object of myv invention to provide for he room air inlet anddischarge of an air conditioning unit an improved muiller and filtersystem and apparatus that is `economical in manufacture and maintenance,is eillcient both in filtering and in silencing noise while at the sametime oiering minimum resistance to the air ow, is compact and pleasingin appearance' and can be readily removed for cleaning or inspection. Afurther object is to provide an improved ltermuliler adapted toeffectively direct and distribute air into the room and into the inletof the blower.

Other objects and advantages will be more apparent to those skilled inthe art from the following description of the accompanying drawings inwhich:

Fig. 1 is a perspective of a self-contained air conditioning unitembodying my improved muffler system, parts thereof being broken away toshow details of construction; Fig. 2 is a plan view of the dischargemuiiler With the infiowing baiiles omitted for sake of clarity;

Fig. 3 is a transverse section on the line 3-3 of Fig. 2;

line 4 4 of Fig. 1;

Figs. 5, 6, 'l and 8 are rear intake lter-muillers.

In the particular embodiments of the invention which are shown hereinmerely for the purpose of illustrating certain specific forms amongpossible others that the invention might take, I have shown in Fig. 1 anair conditioning unit generally 50 indicated at I of any suitable type,although specifically of the form shown in application of H. L. Galson,Serial No. 648,772, tiled December 24, 1932. The specic construction ofsuch a unit does not constitute a part of my present 55 invention. Henceit will sumce to state that the Views of modified Fig. 4 is a verticalfragmentary section on the unit contains a compressor, an air cooledcondenser, an evaporator, and blowers, one for circulating room air overthe evaporator and another for circulating outside air over thecondenser, although it will be apparent that my improved muming andfiltering system is applicable to remote coolingunits having only acooling element without the compressor or condenser, as well as beingapplicable to the inlet and discharge openings for various types ofpassages. However, the invention is particularly applicable to the unitherein disclosed as it has in one end a room air inlet 2 communicatingwith a blower 3 and an evaporator passage which terminates in ahorizontal outlet 4. 'I'his outlet lies in the top surface of themechanical structure of the unit and is specifically of elongated form,Fig. 2, located forwardly of the unit but does not extend for its fulllength. A cabinet 5 entirely encloses the mechanical construction of theunit and is provided with a large rectangular opening 6 in 20 one end toreceive the inlet muiiier generally indicated at 1.

The inlet mufller comprises a relatively large rectangular frame havingan end panel 8 and side pieces 9 extending entirely around the panel 25edges, this relatively shallow box-like construction being open on itsinner side. Disposed near the top of the panel is a series of preferablyvertically elongated openings I0 between which, on 30 the inside of thebox, are a series of vertically extending short bailles I I and a pairof substantially centrally located long baliles I2 all equally spaced inparallel relation and at right angle to the panel. 'I'he foregoingbailies are covered with any suitable sound absorbing material such asshown in application of mine, Serial No. 36,502, filed August 16, 1935,such material also functioning as an impact filter. All of the balilesextend from the inner face of front panel 8 to the plane of the outeredge of side Apieces 9.

On the discharge side of the unit, the cabinet is, provided, Fig. 1,with a top portion I4 and a raised outlet portion I5 at theV rear of thecabinet, extending for the full length of the unit in vertically spacedrelation to vthe top of passage I. Disposed within and extending for thefull length of the raised outlet I5 is 'an upper series oflongitudinally extending and slightly forwardly inclined baflles I6while a lower series of rearwardly inclined longitudinal bailles I'I areplaced with their upper edges substantially adjacent the lower edges ofthe upper baiiies I6, l thereby forming substantially parallel V-shapedair flow passages. 'I'he lower edge of the series 55 of bailles |I issubstantially in the plane of top I4 whereby air discharged fromevaporator passage 4 first flows, as indicated by arrow line |8, Fig. 1,into the common chamber I9 and thence rearwardly therein to bailles I6and |I which direct the air forwardly into the room. To insure uniformdistribution of air in chamber I4 and outlet I5, there is provided avertically extending but angularly disposed baille 20 within chamber I9.This baille overlies evaporator outlet 4 about midway of its length andextends vertically from beneath top I4 down to the inner top surface 2|of the unit in which outlet 4 terminates, thereby compelling air fromthe two divided portions of outlet 4 to be equally distributedthroughout the length of the elongated outlet I5.

In the operation of the apparatus, room air flows inwardly through theseries of openings I and thence downwardly through the parallel passagesformed between the series of vertical bailles and I2. The air uponleaving the end of baiiles turns laterally inwardly to fan inlet 2 whilethe air flowing downwardly between bafiles I2 turns directly into theinlet. 'Ihe bailles areA shorter than baffles I2 due to the necessity ofthe air turning laterally from bailles into the blower inlet 2, butbailles I2 insure symmetrical flow of air into inlet 2. The air thenceflows upwardly through the evaporator passage 4 and is turned rearwardlyas indicated by line I8, Fig. 1,- and is longitudinally distributed byangular,baiile 2|), Fig. 2, and then flows upwardly first through thelower rearwardly inclined baffles I'I and then forwardly through upperbailles I6, Fig. 1. Due to all of the foregoing inlet and dischargebaliies being covered with silencing material preferably of the typedisclosed in said previously mentioned application of mine, it is seenthat the air travels over a very large area of muffler surface with auniform and continuous flow through such baille passages. It has beenfound that such an arrangement emclently muiiies any ynoise and filtersthe air while at the same time permitting eiiicient air flow through theunit.

It will, of course, be understood that various modified arrangements ofthe bailles may be employed while retaining the broad principles asherein disclosed, and certain of these arrangements are shown in Figs.to 8. In Fig. 5, a series of staggered bailles 25 are provided withinthe box I. Instead of having a series of openings |U as shown in Figs. 1and 4, a single elongated opening 26 is provided and also the lower endsof bailles 25 preferably terminate short of the blower inlet whoseposition is diagrammatically indicated by a dotted circle 26. In Fig. 6,a series of zig-zag bailles 2l are provided between the inlet 28 andblower while a pair of angular bailles 29 are provided in the lowermostcorners of the box l. In Fig. '1, a longer air flow passage is providedin box I by having the room air inlet in the loweredge as indicated at30 from which the air flows upwardly along the outside of angularbailies 3| disposed substantially tangent to the periphery of inlet 2and thence around the upper ends of said bailes 3| and down through aseries of vertical bailles 3l. illsV which is not only pleasing inappearance but is relatively simple and economical in manufacture,maintenance and operation and which has the further function ofoperating as an impact lter whereby the long travel of air over themuiller surfaces will permit dirt to adhere to such surfaces andthuslter the air.

It will of course be understood that various changes in details` ofconstruction and arrangement of parts maybe made by those skilled in theart without departing from the spirit of the invention as set forth inthe appended claims.

I claim:

1. A muliling system for an outlet of an air flow passageway comprising,in combination, means forming a chamber into which the air initiallyflows from said outlet, and means forming outlet baille passages ofsubstantially V-shaped formation communicating with said chamber todischarge the air in a predetermined direction.

2. A muilling system for the inlet and outlet of an air flow passagecomprising, an elongated baille chamber one end of which communicateswith the inlet of said passage and the other end of which has airadmission openings, a series of substantially straight baffles formingelongated passages extending from said admission openings to saidpassage inlet, means forming a chamber over the outlet of said passage,and means forming a, series of baille passages communicating with saidchamber so as to freely discharge air therefrom in a predetermineddirection.

3. A muilling system for an air flow passage having an outlet, meansforming a chamber disposed over and also extending laterally of saidoutlet including an upper wall immediately over said outlet in spacedrelation thereto, and a plurality of silencing baille passages locatedabove and communicating with said laterally extending portion of saidchamber, whereby the air flows upwardly through said outlet into saidchamber at a point beneath said upper wall and then laterally and thenceupwardly through said baille passages to be discharged therefrom in agiven direction as determined by said bailles.

4. The combination set forth in claim 3 further characterized in thatsaid chamber extends ber in only one of said laterally disposedportions. thereof.

5. A muilling system' for an air flow passage in an air conditioningunit having an Aoutlet in the top thereof but of shorter length andwidth than that of the unit, means forming a horizontal chamberextending for the full length and width of the unit and having a portionoverlying said outlet, and means forming a plurality of silencing baillepassages along one longitudinal side of said chamber and adapted todischarge the air forwardly toward the other longitudinal side of theunit.

6. The combination set forth in claim 5'further characterized by theprovision of an angular baille overlying the outlet of said passage fordistributing the air to longitudinally spaced portions of said baillepassages.

7. A muilling system for the inlet passage of an air flow passagecomprising means forming an elongated chamber one end of which overliesand is wider than said inlet and the other end of which is provided withair admission openings, a plurality of silencing bailles disposed withinsaid/chamber and extending in the direction of elongation thereof,certain of said baifles being of suicient length to extend directlyover4 said inlet and other of said bailles being of shorter enclosingsaid unit and having an opening therelength adjacent said inlet, wherebythe elongated in adjacent the inlet of said air ilow passage,

baffles cause air to ow directly to said inlet while means forming achamber removably disposed in the shorter bailles permit air to turnlaterally said opening, means forming a series of silenc- 5 from theirshortened ends into said inlet. ing baille passages within said chamber,and 8. A muiling system for the inlet of an air means providing an airadmission opening in said ow passage extending through an airconditlonchamber forming means. ing unit comprising, in'combination, a'cabinet ALFRED WEILAND.

